1. Field of the Invention
This invention is generally directed to power transmissions for automotive vehicles and particularly to a continuously variable turbo mechanical transmission having a primary input drive train disposed between a vehicle power source and a vehicle drive shaft and a fluid torque converter supplemental drive train cooperatively engaged to transmit drive torque to the primary drive train at engine speeds in excess of normal idling speeds, and in which the fluid torque converter is mounted along a portion of a reversely directed torque compensating drive train to thereby absorb engine torque being transmitted towards the vehicle drive shaft from the primary drive train at low engine speeds.
2. History of the Prior Art
In the present day automatic transmissions for automotive vehicles torque from the vehicle power source to the vehicle drive shaft and hence to the drive wheels of the vehicle is regulated through a set of automatically shiftable gears which are engaged or disengaged upon the detection of various driving and loading conditions. Such automatically shiftable gears are regulated by vacuum operated modulaters, drive shaft governors or other throttle controls to vary the torque ratio between the power input and output shafts depending upon the amount of torque being introduced into the transmission. In the operation of such automatic transmissions, as torque is increased from the engine drive input, the transmission responds at various predetermined conditions to alter the gear ratio between the engine input and the vehicle drive shaft so as to approach a theoretical one to one relationship between the input and output of the vehicle drive train.
A problem frequently encountered with automatic transmission is that at low engine idling speed the torque generated by the power source is imparted to the vehicle drive shaft resulting in a condition known as "creep". Under such conditions, the automotive vehicle operator must apply the brake to the vehicle while stopped at stoplights, parking areas, intersections and the like. In the event the vehicle brake is released prior to acceleration, the torque developed at the idling speed is sufficient to be transmitted through the transmission to the vehicle drive shaft and thus the vehicle is urged into a driving mode even though the accelerator is not engaged.
Various prior art transmissions have been developed to overcome problems associated with standard transmissions by providing means for absorbing engine input torque until vehicle acceleration is desired. Such transmissions may incorporate a combination of fluid torque converters together with mechanical gearing systems. Some examples of the prior art include U.S. Pat. Nos. 2,675,137 to Place; 2,704,468 to Horton et al.; and 2,834,228 to Place.